Many surgical and other therapeutic or diagnostic procedures include steps of reconfiguring, fixing, or otherwise manipulating tissue in some manner, or joining two or more portions of tissue together. Several devices have been used to perform these functions, including sutures, staples, screws, anchors, clips, tags, and other similar types of devices.
Many of the conventional sutures, staples, clips, tags, and anchors that are used in these procedures require extensive training by the clinician to achieve competent use. In addition, many of the devices concentrate significant force over a small surface area of the tissue, thereby potentially causing the suture, staple, or anchor to tear through the tissue.
Many of the procedures require regions of tissue within the body to be approximated towards one another and reliably secured. For example, several surgical procedures are performed in which tissue in the gastrointestinal lumen is approximated, such as gastric reduction. The gastrointestinal lumen includes four tissue layers, wherein the mucosa layer is the inner-most tissue layer followed by connective tissue, the muscularis layer and the serosa layer. One problem with conventional gastric reduction systems is that the anchors (or staples) should engage at least the muscularis tissue layer in order to provide a proper foundation. In other words, the mucosa and connective tissue layers typically are not strong enough to sustain the tensile loads imposed by normal movement of the stomach wall during ingestion and processing of food. In particular, these layers tend to stretch elastically rather than firmly hold the anchors (or staples) in position, and accordingly, the more rigid muscularis and/or serosa layer should ideally be engaged. This problem of capturing the muscularis or serosa layers becomes particularly acute where it is desired to place an anchor or other apparatus transesophageally rather than intraoperatively, since care must be taken in piercing the tough stomach wall not to inadvertently puncture adjacent tissue or organs.
One conventional method for securing anchors within a body lumen to the tissue is to utilize sewing devices to suture the stomach wall into folds. This procedure typically involves advancing a sewing instrument through the working channel of an endoscope and into the stomach and against the stomach wall tissue. The contacted tissue is then typically drawn into the sewing instrument where one or more sutures or tags are implanted to hold the suctioned tissue in a folded condition known as a plication. Another method involves manually creating sutures for securing the plication.
One of the problems associated with these types of procedures is the time and number of intubations needed to perform the various procedures endoscopically. Another problem is the time required to complete a plication from the surrounding tissue with the body lumen. In the period of time that a patient is anesthetized, procedures such as for the treatment of morbid obesity, GERD, or other procedures must be performed to completion. Accordingly, the placement and securement of the tissue plication should ideally be relatively quick and performed with a high level of confidence.
Another problem with conventional securement methods is ensuring that the staple, knotted suture, tag, anchor, or clip is secured tightly against the tissue and that the newly created plication will not relax under any slack which may be created by slipping staples, knots, or clips. Other conventional tissue securement devices such as suture anchors, twist ties, crimps, etc. are also often used to prevent sutures from slipping through tissue. However, many of these types of devices are typically large and unsuitable for low-profile delivery through the body, e.g., transesophageally, transrectally, or transvaginally.
Moreover, when grasping or clamping onto or upon the layers of tissue with conventional anchors, sutures, staples, clips, etc., may of these devices are configured to be placed only after the tissue has been plicated and not during the actual plication procedure.